Science Driven CRO

Science Driven CRO


The 5W1H Approach to
Writing a Clinical Study Protocol

An age-old writing methodology based upon the thoughts of Aristotle, the Ancient Greek philosopher and scientist who was Plato´s student and who later taught Alexander the Great, is as applicable to today´s technologically advanced biopharmaceutical research sector as it has been throughout history.

This 5W1H formula constitutes the writer´s toolkit for getting a complete idea of a subject and knowing what exactly has happened or, when planning to do something, what should happen. It refers to the six simple, but essential, questions that can be applied to the development of a Clinical Study Protocol. These questions are:

  • Who?
  • What?
  • When?
  • Where?
  • Why?
  • How?

From the title of the study to the last page of the Appendices, the Protocol should clearly identify the answers to these questions.


The protocol should identify everyone involved in the study. Questions include: Who are the patients? Who are the investigators? Who is responsible for each of the many other tasks that make up the study?


We need to ask and answer: What is the study about? What is the therapeutic indication? What is the study drug? What is the route of administration? What should be done if an SAE is reported?


The protocol needs to clearly answer the following: When will the study commence? When will the study procedures and visits take place? When will the study end? When should x be performed?


Where is the setting of the study? Where are the sites?


This question should be kept in mind and inform every part of the protocol. Why is the study being performed? This question is answered in detail in the Introduction, Background, and Rationale sections. This concise review of why the study is being performed would incorporate a review of the literature, an analysis of the risk-benefit ratio and, most importantly, why the current research would benefit society.


Once we have a clear idea of what we intend to achieve, why we are doing the study, with the help of whom, and when and where we will do it, we have set the stage for detailing how the objectives will be met.

The study design, study procedures and planned data analysis sections should give sufficient instructions on how the study is to be conducted, how the results are to be collected, and how the data are to be analysed.


This age-old formula was effective in the field of Aristotelian Ethics thousands of years ago and has remained effective to the present day. Applying the 5W1H approach to drafting a Clinical Study Protocol ensures that well-crafted hypotheses and objectives, with suitable endpoints, can be communicated clearly. A well-written protocol is key to increasing the likelihood that the appropriate study procedures are followed in the same way by all personnel at multiple sites. This will, in turn, enable high quality data to be collected that can lead to scientifically sound conclusions and give the drug development strategy the best chance of success, whilst bringing new treatments to patients that much sooner.

Further Reading

Aristotle Biography: Click to read [Online] (Accessed: 12 November 2019)

International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH Harmonised Guideline integrated addendum to ICG E6(R1): Guideline for Good Clinical Practice E6(R2). 2016: Click to read [PDF] (Accessed: 12 November 2019)

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Neil Goodman

Neil Goodman, PhD, BSc(Hons) 
Senior Medical Writer

T: +32 9331 6030
E: [email protected]